Discrimination of nuclear and electronic recoil events using plasma effect in germanium detectors

TL;DR

This paper introduces a novel method using plasma time differences caused by the plasma effect in germanium detectors to distinguish nuclear from electronic recoil events, aiding rare physics searches.

Contribution

It presents a new plasma time difference technique and a numerical model to differentiate recoil types in germanium detectors, enhancing detection capabilities.

Findings

Plasma time difference can be sufficiently large for discrimination.

Numerical model accurately predicts plasma times at various energies.

Potential for practical implementation in rare event searches.

Abstract

We report a new method of using the plasma time difference, which results from the plasma effect, between the nuclear and electronic recoil events in high-purity germanium detectors to distinguish these two types of events in the search for rare physics processes. The physics mechanism of the plasma effect is discussed in detail. A numerical model is developed to calculate the plasma time for nuclear and electronic recoils at various energies in germanium detectors. It can be shown that under certain conditions the plasma time difference is large enough to be observable. The experimental aspects in realizing such a discrimination in germanium detectors is discussed.